 When Kars Veling, the party's "lijsttrekker", stepped down as a result of the election loss, Slob took his place.He was put on the second place of the list of Christian Union candidates for the 2004 election and was reelected.After the 2006 general election, Slob and party "lijsttrekker" André Rouvoet represented the Christian Union in the negotiations for the formation of the new cabinet of the Netherlands, the Fourth Balkenende cabinet; Rouvoet was appointed Deputy Prime Minister of the Netherlands.